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What can I expect from my 3in telescope?

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xdknightx

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I bought an Astromaster 76eq 3in reflecting telescope with a 10mm eyepiece?
http://www.celestron.com/c3/product.php?ProdID=424

I aimed my telescope at what I think was Mars at its closest to earth (I believe Jan 29th).

All I saw was an orange twinkling star no different from any other star except for the color.

I was expecting to see a small round orangy form (minus the twinkling).

Am I expecting too much? What should I expect from my telescope? Did I buy a piece of junk?
 
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OleNewt

Guest
Planets don't twinkle, only stars do. The twinkling has something to do with the fact that stars emit light whereas "dark" bodies like planets merely reflect it.
 
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crazyeddie

Guest
xdknightx":14aapxf3 said:
I bought an Astromaster 76eq 3in reflecting telescope with a 10mm eyepiece?
http://www.celestron.com/c3/product.php?ProdID=424

I aimed my telescope at what I think was Mars at its closest to earth (I believe Jan 29th).

All I saw was an orange twinkling star no different from any other star except for the color.

I was expecting to see a small round orangy form (minus the twinkling).

Am I expecting too much? What should I expect from my telescope? Did I buy a piece of junk?
Well, it's not a "piece of junk", but it's only one step up from a toy telescope. Mars is one of the most difficult objects to observe, even for experienced amateurs. It requires high magnification to get even a glimpse of surface detail. You would need at least a 6 to 8" reflector or a 5" refractor or catadioptric telescope, at a minimum, to observe Mars as anything other than a tiny orange blob. I'm afraid your 3" reflector is not up to the job. It's fine for looking at the moon, though, and maybe Jupiter, Saturn, Venus, and open star clusters.
 
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Jazman1985

Guest
A couple months ago I decided to make myself a 5.5" reflector, still working on getting the mount set up correctly for stability and aiming, but the coolest and easiest thing to spot(as far as I'm concerned at least) is either saturn or jupiter, dependent on where you are on the planet earth(North America?), you should be able to see saturn late at night and the andromeda galaxy a little earlier. You won't be able to see much of mars with a 3" reflector, think a few pixels on your computer screen. I'd say a much better judge of your scope would be to just try it out on the moon, and an individual star. If you can bring them both into clear focus then there's nothing wrong.
 
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ramparts

Guest
OleNewt":u46uzo5e said:
Planets don't twinkle, only stars do. The twinkling has something to do with the fact that stars emit light whereas "dark" bodies like planets merely reflect it.
Light is light, whether it's emitted or reflected should make a difference. Notice that the Sun doesn't twinkle. The reason is that the planets are close enough that they look big on the sky; even though stars are much bigger, they're so much farther away that they're essentially what we call point sources, which is, we can't distinguish their shapes. There's a sort of averaging out of light in the atmosphere; since the planets look bigger and have some extent on the sky, light from one part of the planet will "cancel out" the twinkle that might arise from another part. But since stars don't really appear to have spatial extent in our sky, the same thing can't happen.
 
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xdknightx

Guest
Thanks everyone for your replies. I wish I would have joined this forum before buying my telescope (it's too late to return it now).

"...I'm afraid your 3" reflector is not up to the job. It's fine for looking at the moon, though, and maybe Jupiter, Saturn, Venus, and open star clusters."

Judging by CrazyEddie's reply (see above); it would be easier to see Jupiter and Saturn rather than Mars. Why is that? Jupiter is much larger but also much further away than mars.
 
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MeteorWayne

Guest
It's much larger in the sky. Despite it's greater distance, it's so much bigger it gets much larger than Mars ever can. Saturn's rings can get almost as large as Jupiter's disk. The other really large planet is Venus; you can't see any detail on the surface, but it goes through phases just like the moon, so changes shape.

Right now Jupiter is about 4 times larger than Mars.
 
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xdknightx

Guest
Thanks MeteorWayne.

I'm using TheSkyX software and I see that tonight Saturn should be visible for me after 9pm.

Any ideas of what to expect and how to find it?

Finding objects in the sky is the real challenge. I live in a suburb of Montreal, so there is some light pollution but not that much.
 
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MeteorWayne

Guest
Well, it's the brightest object in that part of te sky, it's in the constellation Virgo, which is hard to see (except for the brightest star Spica) under light ploouted skies. Do you know any constellations at all? If you tell me ones you recognize, perhaps I can use them you point you in the right direction.

Wayne
 
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xdknightx

Guest
I know the constellations in software but I've had HARDEST time trying to identify them in the night sky.

I usually try to find Polaris first (Ursa Minor; Little Dipper) and then move away towards whatever I'm looking for but I've had limited results.

I guess I should try to spot Leo and go down towards the right from the tailend. Is saturn visible to the naked eye?
 
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MeteorWayne

Guest
Yes Saturn is easily visible to the naked eye. In fact, once you know it, you can identify it easily anytime it's in the sky because:

It's on the ecliptic (the path of the Sun Moon, and Planets).

It's a planet, so doesn't twinkle unless very close to the Horizon.

It has a very distinctive creamy white color.

At 9PM it will be about 30 degrees to the right of the bright star Arcturus, and be the brightest thing in the area. To find Arcturus follow the curve of the Big Dipper's handle in the direction away from the bowl. The bright star that curve intersects is Arcturus. It will be about 20 degrees (two fist widths with your arms extended) above the horizon. As you said, Saturn will be directly below Leo.
 
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xdknightx

Guest
Thanks MeteorWayne for you tips.

Although I was still not able to discern any constellations (probably due to a greater amount of light polution than I had originally thought), I still was able to find Saturn quickly because it was the only object in that part of the sky that wasn't twinkling!

After a few seconds I was able to put it in focus. I was able to see a small white ball only a few pixels in size and I could also see a white disk. I'm happy with that result seeing that my expectations have been greatly reduced.

One thing is curious. I could see saturn but when I try to focus on it, I can also see saturn's "shadow" behind it and to the right. I'm thinking this is an issue with the alignment of the mirrors or something.
Any ideas on what that shadow could be?
 
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MeteorWayne

Guest
Are you sure you weren't seeing the rings? While they are thin right now, they should be visible.

And is your telescope a refractor (lenses) or a reflector (mirror at the bottom). If it is a reflector, collimation may improve the image. If it's a refractor and the lenses are mislaigned, there's not much you can do.
 
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xdknightx

Guest
The rings were visible too.

What I was seeing was a second saturn which was dimer, behind and to the right. Like two identical images that weren't aligned or superimposed.

My telescope is a reflector. SWhat is collimation?
 
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MeteorWayne

Guest
Collimation is aligning the main mirror so it points exactly at the secondary mirror, and aligning the secondary mirror so it points exactly at the center of the eyepiece. Did your scope come with instructions on the procedure?
 
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Fallingstar1971

Guest
All I saw was an orange twinkling star no different from any other star except for the color.
Im betting you discovered the constellation Bootes.......

That bright star is Arcturus. You are not the first to mistake this for Mars. At the time Saturn is rising, Mars is almost overhead.

Planets do not twinkle. However, everything they said about mars it true. You will see a small red disk. Very small. Even my 4.5 Celestron could not make it more than a very small red disk.

My XT8 can make out more details (ice caps), and the filters can tease out a little more.0

3inch is good to start though. Your 3 inch scope, used every night, will give much MUCH better views than a 14inch scope that never leaves the closet because the owner cant deal with moving that much weight.

1/2 inch scope to 100 inch scope doesnt matter........

What matters is that you USE it. Go to some star parties. If your in New England were supposed to have partly cloudy skies tonight with clear skies tomorrow. Its been WEEKS since we've had clear skies, and I am looking forward to it. If your local, then your more than welcome to come and look through mine.

(my very first scope was a 2.5 inch "Railroad Salvage" special. But it was enough to light the spark. I saw a crescent Venus that night for the very first time.)

Now, I use a hand cart, a packing mold, and a bungie cord to move my scope. Just tilt and walk :)

Seriously, go to a star party. Look and see. If your expectations are too high even a 40 inch scope would not be enough. If you like what you see, then I suggest moving on up to a 4 or 6 inch scope(<-------go with the 6). Personally, I would stay away from the smart scopes. IMO, they are for people that cannot read a map. Learn the hobby, buy a amateur astronomy book. Pick up a cheap pair of Binoculars and learn the book of the sky. Practice star hopping. Try going to the first star in the handle of the big dipper and hop your way all the way to the bowl without looking away from the eyepiece. Master these skills now and it will be much easier if you should decide to buy that bigger scope. You should be able to see most of the big dipper, even under modest light pollution. Once you master the constellations, planets are now EASY. They are the "Stars" that dont belong. So if you see an extra "star" where one shouldn't be, then its either a planet, nova, or supernova. If it changes position over time, its a planet. (wanderers)

There are some UHC filters that may help with the pollution problem. They filter out the wavelengths of light that street lights..ect use. HOWEVER, its a filter and some stars and nebula's USE these wavelengths.

I do not know what eyepiece size your scope takes, I googled your "ghosting" problem and it seems that the fault could be with your Eyepieces. However, if they are smaller in diameter than 1.25 inches then I wouldn't bother. Save your money for a scope that takes 1.25 inch EP, These are "standard" EP size and most accessories are set for either 1.25 or 2inch diameter EP.

Collimation, as MW said, is aligning the mirrors. You start with the secondary (little one) and then align the primary (big one) at the secondary.

Sounds scary, but its very easy once you learn how. My first time took me over an hour. Once the secondary is aligned, unless you drop or bang the scope hard, it will stay that way.

Primary is different. Check alignment right before you go outside. You can just pick this up and carry it, so banging it into something should not be a problem (there is a handle on mine, but using it causes the tube to swing uncomfortably close to the ground. Thats why I have a cart)

http://www.oarval.org/collimatE.htm (descent site that will teach you how)

Enjoy

Star
 
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MeteorWayne

Guest
Thanx eddie, I used to have that link but it's on the dead hard drive :(
 
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Fallingstar1971

Guest
OK are you ready for this?

Fire up your software, pan to Ursa Major, and look for M81.

Zoom your software to 20X and look closely at the two Galaxies right next to each other.

Now zoom your software back out to normal, and look closely at where m81 is in relationship to the stars in the bears head. Either print a map from your software or google Ursa Major and print a map that way) At my location at around 8ish, Ursa Major is perpendicular to the horizon (90 degree angle, constellation is almost straight up and down). Look at the stars in the bears head. Now look at your map. Look back at the sky, and picture your map AS the sky. For me, if I take my left hand relaxed, and place my thumb over Dubhe (top right hand star in the dippers bowl) These two galaxies are about where my left pinky is.

Or

Start at Dubhe, look twords the bears nose. Note where the next star up is from Dubhe. Aim your scope at a point just over half the distance to the next star up from Dubhe. Make a mental note of this spot. Now, find the last star in the tail of draco. Trace an imaginary "up" from this star. Trace a line west from the other spot in the big dipper. Where the two cross will put you very close to where these galaxies are. They are just a bit dimmer than Andromeda, so if you can see M31 in Andromeda you should be able to at lest make out the shapes of these two. They are close enough together to capture in the same field of view, so you can see them both at the same time without moving the scope (25mm EP)

Or

You have setting circles that can get you fairly close, then just slowly pan the scope around until you find them.

Myself, I just look at the map, and picture the sky as my map, and it usually doesnt take more than ten minutes before I have found what I am looking for. Print maps, mark on map your goals, take map + RED flashlight with you.

Why red?

Because red light doesn't spoil your night vision. It can take up to an hour for your eyes to fully adjust to the night, (this is key as well). Just one car, one glance at a streetlight, one cigarette lighter, even for a second, resets your eyes to daytime and they need to adjust all over again. So RED light whenever possible.


Star
 
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SpaceTas

Guest
Yes Mars is a tough planet to observe: under good conditions (low twinkling = "seeing") when Mars is really close to the Earth and your telescope is well collimated you should be able to see Sytris Major and the polar cap.

Jupiter is a good target. Again under decent conditions you'll be able to see the main belts/zones. With a equivalent telescope I only spotted the hollow of the red spot a few times. The Galiliean moons are obvious.
Saturn when rings are open should be able to pick different rings and Cassini division as well as white equatorial belt( just).

Don't forget the obvious MOON!

I recommend moving along the Milky way looking at each fuzzy patch you see with your eye or in the finder. You'll discover many beautiful open clusters and bright nebulae.

Then chase down some globular clusters, the ring nebula, a few galaxies.

That's several years worth.. :geek:

Collimation. This is aligning the mirrors of your reflector. The centers of the main mirror, secondary mirror and eyepiece need to be aligned. The instructions are probably buried at the back of the instructions. on the web look for instructions for a Newtonian telescope. You'll need to find the set that makes sense to you.

Quick checks:
Take the eyepiece out: point the telescope at a bland scene, sky evenly illuminated wall. If the images of the mirrors, side of tube, spider looks all concentric, the alignment is close otherwise .... As a newbie you'll only spot obviously wrong alignment.

If when you focus a star, it has a little tail on it; the alignment of the optics is out. The star test is very sensitive. Once it is right you'll get the best out of the optics you've got.

People of your local astronomical society can help with this and getting to know the sky.
 
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